The present invention relates generally to operations performed and equipment utilized in conjunction with a subterranean well and, in an embodiment described herein, more particularly provides downhole pressure balanced electrical connections.
It is known to enclose lines, such as electrical and optical lines, in pressure-bearing conduits to protect the lines from well fluids in a subterranean well. Typically, the conduits isolate the lines not only from the damaging, corrosive and/or electrically conductive fluids, but also from the pressure exerted by the fluids in the well. The pressure might be hydrostatic and/or applied pressure.
Unfortunately, the need to isolate the lines from pressure leads to several problems in making connections in the lines downhole. For example, pressure-bearing connectors must be used at each connection, and each connector must be capable of reliably withstanding the entire hydrostatic and applied pressure in the well.
Another problem is that the conduit itself must be designed to withstand the entire hydrostatic and applied pressure. Thus, relatively expensive materials and highly reliable designs must be used for the conduit and connectors.
A system has previously been available in which the conduit is filled with dielectric fluid. The dielectric fluid is pressurized from the surface via a pump. However, this system requires that the pressure be transmitted all the way from the surface, which may in some cases be thousands of meters from a downhole tool to which the lines are connected.
Therefore, it may be seen that improvements are needed in the art of protecting and insulating lines in subterranean wells.